Resinous impregnating material



mama Aug. so, 193s UNITED STATES PATENT OFFICE 2,128,879 BESINOUS IMPBEGNATING MATERIAL Kenneth M. irey an sadel Park, N. 1.,

ration, New York, N.

No Drawing. A

inous impregnating d Lawrence M. Debing, Paliasslgnors to Resinox Corpo- Y., a corporation of Delappllcation November 14, 1936, Serial No. 49.138

g '1 Claims. (01. 106-2!) Our invention relates to the production of resmaterials. More specifically,

our invention relates to the production of an improved impregnating material having a resinous base formed by the condensation of aldehydes with bis- [hydroxy aryl] di-alkyl methanes and/or their ketone condensation produc having phe- Numerous impregnating agents nolic resin bases have been recommendedin the past but these have in most cases been prepared by the reaction of aldehydes with free phenols or materials containing free phenols.

Such products are, therefore, disadvantageous for many P rp especially for impregnating objects which come in contact with foodstufls.

One object of our invention, preparation of a resinous therefore. is the impregnating material having as a base a condensation product of substances containing no free phenols. A further obm ject of our invention is the preparation of an impregnating material which, upon application and heat treatment. will have satisfactory bonding properties, flexibility,

toughness, and water resistance. Further objects and advantages of our invention will be apparent from the following description.

The impregnating agents of our invention comprise suspensions, in vents, or plasticizers,

relatively non-volatile solof heat reactive condensation products of aldehydes with bis- [hydroxyaryll-di-alkyl methanes, or mixtures of such substituted methanes with their ketone condensation products. Weprefer to: employ such a mixture,

as for example, a

mixture of beta.beta-bis-[4- hydroxy-phenyll-propane and beta.beta-bis-[4- hydroxy-phenyll -propane-'-acetone condensation product. Mixed reaction products may be formedby the interaction aryl compounds and ketones. aryll-di-alkyl methane constitutes crystalline reaction product of 2 of this type of hydroxy- Bis- [hydroxythe primary mols of the corresponding hydroxyaryl compound with 1 mol. of a ketone.

Bis- [hydroxy-aryl] -di-alkyl methane-ketone condensation product represents the further reaction of the primary with additional ketone.

prepared separately and subsetalline product products may be quently mixed as described below, or

crys- These a mixture of the materials may suitably beprepared in a single 50 reaction from the. corresponding .hydroxy-aryl compounds and ketones, in accordance with the process described in co-pending application Serial No. 680,230 by K. M. Irey and L. C. Swallen. The

method of preparing the compounds separately 5 and subsequently mixing is described in the extions of acetone and the crystalline product de- 15 scribed above, in the presence of an acid catalyst such as hydrochloric acid, at'temperatu'res of '70 to 80 C. This material may also be prepared by any other suitable procedure as, for example, that disclosed in co-pending application U. 8. Serial No. 680,230 referred to above. The beta.beta-bis- [4-hydroxy-phenyll-propane-acetone condensation product prepared by anyof these procedures is a reddish colored resinous material having a melting point around 50 C.

The mixed intermediate which we' prefer to utilize in the present process cpnstitutes a mixture of approximately equal proportions of the beta.beta-bis- [4-hydroxy -'phenyll-propane and the beta.beta-bis-[4-hydroxy-phenyll-propaneacetone condensation product. This intermediate may be prepared by simply mixing the materials prepared as above described, or, as has been pre-' viously pointed out, this intermediate may be formedin a single reaction fromthe correspond- .35 ing hydroxy-aryl compound and hetone. The proportions of the two ingredients of the mixed intermediate may be varied within rather wide limits and, in fact, either one of the materials may beused separately. However. in general we 40 prefer to utilize a mixture of approximately the proportions described above.

The second step of the process for preparing our improved impregnating materials constitutes the reaction of the mixedintermediate product described above with an aldehyde such as formaldehyde or one of its polymers. This reaction is carried to a definite stage as indicated by the dry rubber". test, after which the product is immediately mixed with a high boiling solvent,

or plasticizer, to yield the final impregnating material. The "dry rubber" test utilized in this connection measures the degree of heat reactivity of the resinous product in terms of the time required to eliminate tackiness in a sample placed employed as condensation catalysts, give rise to a marked acceleration of the reaction but nevertheless require a considerable period of time to carry the reactionto the preferred stage for the present process. We have found that lime exerts a more pronounced accelerating eflect and that a mixture of lime and barium hydroxide constitutes an eminently satisfactory catalyst for this purpose. four parts of of lime, this reaction may generally be carried to the desired stage in a period of about 30 minutes. Although we prefer to employ a mixture of this nature, it may be said that any alkaline earth catalyst will be operative in our process.

The condensation reaction may be illustrated by the following specific example: 100' parts of the mixed intermediate product described above are placed in a resin kettle, melted and then cooled to approximately 60 C. The mass is then thoroughly mixed with '70 parts of a 40% formaldehyde solution after which 4 parts of barium hydroxide and one part of lime are added in the form of-an aqueous suspension. The resulting mixture is then reacted under heat until a sample exhibits a dry rubber test of approximately 15 to 25 seconds. When this point is reached, the application of heat is immediately stopped and the plasticizer, e. g., diethylene glycol, is added as quickly as possible. The amount to be added will depend upon the desired plasticity of but for most Utilizing a'catalyst comprising purposes should be just suflicient to bring the material to the state of a thin liquid having a dry rubber test of approximately '40 seconds. a

The dry rubber value of the material maybe varied within rather to 90 sec., depending heat reactivity of the poses it is preferred I this stage as far as possible without transforming the product to the insoluble or rubbery stage. The dry rubber test of 15 to 25 seconds represents a safe practical limit, but the reaction may, of course, be carried further if precautions are taken to cool the material by adding the plas-' ticizer before the insoluble stage is reached.

The plasticizer apparently acts onlyin a physical manner as a solvent or plasticizing agent and wide limits, e. g.. 15 sec. on the desired degree of product. For some purdoes not enter into reaction with the resinous 4 mass. The increased time value of the dry rubber test, after addition of the does not indicate a change in the nature of the cessfully employed.

resin but merely a physical efl'ect ofthe presence of the plasticizer. It will be apparent, therefore, that any other organic solvent-or placticizer for the particular resin produced may be suc- Any such material, however, should preferably be sufl'lciently non-volatile to exerta plasticizing efl'ect in the final mass ""of impregnating material after application and heating, and should, of course, be chemically inactive towards the resinous mass and the materlals to be impregnated.

barium hydroxide and one partthe impregnating material,

to carry the reaction at plasticizing agent which comprises carrying The impregnating agents prepared as above described may be employed for any of the purposes for which previously known materials of this general type have been used, e. 3., as adhesives, coating materials, etc. The usual methods of application may be employed and the usual methods" of heating maybe used to transform the impregnating material to the insoluble stage. For example, various fibrous materials may be coated with the impregnating agent by dipping, brushing, spraying and the like, and may subsequently be baked in an oven until the resinous coating or bond reaches the desired stage of insolubility and toughness. Various other uses, such as the application of an enamel" coating to wire, will also be'apparent to those skilled in the art. The desirable properties of our impre'gnating material will best be taken advantage 01', however, in the impregnation of materials which comein contact with foodstuffs. In such uses the desirable properties of our impregnating agents, such as water impermeability and freedom from taste and odor are highly advantaeous. I

It is to be understood, of course, that our invention is not to be limited to the particular examples given above by way of illustration. Equivalent reactants and varying proportions or reaction conditions may be employed depending upon the exact nature of the product desired. For example, instead of employing beta.beta-bis- [4-hydroxy-phenyl]-propane and its acetone condensation product, any of the homologues of these materials could be employed, Also, in place of formaldehyde, its polymers such as paraformaldehyde or hexamethylene-tetramine, or its homologues such as acetaldehyde could be utilized. Likewise, any suitable high boiling solvent orpla'sticizer', such as glycerine, which is compatible with the resinous reaction product and thewater contained in such product, and which is chemically inactive at the temperatures employed, could suitably be substituted for the diethylene glycol specified in the example. In

general it may be stated that any equivalents or modifications of procedure which would naturallyoccur to one skilled in the art are included within the scope of our invention.

' Our invention now having been described what we claim is:

1. Ina process for the production of a resinous material by heat reacting a mixture of a bis- [hydroxy-aryll-di-alkyl methane and a bis- [hydroxy-aryll-di-alkyl methanHetone condensation product with a sufllcient proportion of an aldehyde to form an insoluble infusible product when fully reacted, the improvement which comprises carrying the reaction to an advanced stage evidenced by a dry rubber test of 15 to 25 seconds, venting substantial further reaction by the application of heat and introducing ticizer compatible with the condensation product thus produced.

2. In a process for the production of a resinous material by heat reacting a mixture of beta.- beta-bis [4-hydroxy-phenyll-propane and beta beta-b'is- [qt-hydroxy-phenyl] -propane acetone condensation product with a sufficient proportion of formaldehyde to form an insoluble infusible product when fully. reacted, the improvement the reaction to an advanced stage evidenced by a dry rubber test of 15 to 25 seconds, and then immediately preventing substantial further reaction by ceasing the ceasing a plas- ,and then immediately preapplication of heat and introducing a plasticizer compatible with the condensation product thus produced. I

3. In a process for the production of a resinous material by heat reacting a mixture of beta.betabis-l4-hydroxy-phenyll-propane and beta.betabis-[*i-hydroxy-phenyl]-propane-acetone condensation product with a suflicient proportion of formaldehyde to form an insoluble infusible product when fully reacted, the improvements which comprise effecting the reaction in the presence of an alkaline earth catalyst containing lime, carrying the reaction to an advanced stage evidenced by a dry rubber test of 15 to 25 seconds, and then immediately preventing substantial further reaction by ceasing the application of heat and introducing a plasticizer compatible with the condensation product thus produced.

4. In a process for the production of a resinous material by heat reacting a mixture of beta.- beta-bis- [4-hydroxy-phenyll-propane and beta.-

beta-bis- [4 -hydroxy-phenyl] -propane acetone condensation product with a suflicient proportion of formaldehyde to form an insoluble infusible product when fully reacted, the-improvements which comprise effecting the reaction in the presence of a catalyst consisting of four parts of barium carrying the reaction to an advanced stage evidenced by a dry rubber test of 15 to 25 seconds, and then immediately preventing substantial further reaction by ceasing the application of heat' and introducing diethylene glycol into the condensation product thus produced in an amount suflicient to increase the dry rubber test of the final product to approximately 40 seconds.

5. The product of the process of claim 1. 6. The product of the process of claim 2.

7. The product of the process of claim 2 characterized by a degree of reactivity evidenced by a dry rubber test of approximately 40 seconds.

KENNETH M. lREY. LAWRENCE M. DEBING.

hydroxide and one part of lime, 

